Method of reclaiming used lubricating oil



H. G. CROWLEY ET A1. '2,045,216

MTHD OF RECLAIMING USED LU'BRICATING OIL June 23,l 1936.

Filed Feb', e. 1933 s sheep-sheet 1 June 23, 1936. r H G. CROWLEY ETAl.A I 2,045,215

METHOD OF RECLAIMING USED LUBRIOATING OIL Filed Feb. 6, 1953 5Sheets-Sheet 2 /L- "S Inni- U, l1

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H. G. CROWLEY ET AL METHOD OF RECLAIMING USED LUBRICATING OIL 3Sheets-Sheet 3 Filed Feb. 6, 1933 45| We have also discovered that theoil after heat Patented lune 23, 1936 UNITEDI STATES PATENT OFFICEMETHOD 0F RECLAIMING USED LUBRICATING OIL vappumid'im February s. 1933,serial No. 655,504

4 emma. (cl. ias-1s)A Y* invention relates to a method and apparatus forreclaiming or reconditioning used lubricating oils and particularly tothe reclaiming of crank case oils, which have become so diluted w'ithlighter hydrocarbons and so contaminated with foreign substances such asdust, particles of metal, carbon, or the like, so as to render themuseless as a lubricant.

In prior process for reclaiming used lubricating oilvsteam or airemployed for agitating the oil in the heating chamber was introducedwhile the oil was being heated. We have discovered, however. that it isadvantageous to iirst subject the used lubricating oil to heat treatmentand discontinue the heating thereof before the steam is introduced intothe body of the heated oil. Among the advantages incident to ourimproved method are the cooling of the oil to a desirable temperaturewhereby the same will not injure the lter paper when introduced to thefiltration zone, minimizing the tendency of cracking of (the oils,preventing the tendency of the heated oils to iiash" when led to thefiltration zone .and avoiding the tendency of slowing down the heatingoperation as would be the case if the steam were intro,- duced duringthe heating step. i

We have also discovered that aportion of the heavier impurities can beremoved from the used crank case oils before subjecting them to theheating and steaming steps above mentioned by the utilization of aportion of the waste heat from the oil from a prior heating andfiltering step to effect a separation of heavygreases and sludge fromthe lubricating and lighter oils contained in the used-oils such thatthe 'oil charged to the heating and steaming step can be moreelcaciously treated. As a result of this improvement the temperature ofthe lered oilis lowered, while producing the important advantage abovedescribed, so as to leave the oil at a desirable temperature for afurther purification step and at a temperature at which oxidizationafter discharge from the process is inhibited.

treatment and filtering still contains a quantity of very finely dividedcarbon and have further discovered that if this oil, after it has hadits temperature somewhat reduced by causing' it to give up some of itsheat `to the oil entering the process for the purpose above stated, iscaused to come into intimate contact with a metal con-v tact surface,the `finely divided carbon is precipitated and removed from the oil.

We have also provided an improved apparatus aninternal combustionengine,

in which our process may be carried out although it is to be understoodvthat the process may be carried out in an apparatus other than thatillustrated.

One object of the invention is, therefore. to 5 provide a method wherebyused crank case oil may be subjected to controlled heating and filteringto separate it from contained impuritiessuch as lighterhydrocarbons'from the cylinders of water, motor. 1o cuttings, dust andcarbon. 4

Another object of the invention is to provide a process for reclaimingusedlubricating oils in which the oil is subjected to heatingand'steam-4 ing,- wherein the heating of the oil is discontinued beforethe steam` is introduced into the body of the heatedoil, to produce theimproved' results above pointed out.

Another object of the invention resides in the provision of a method ofreclaiming used crank 2o case oil wherein the waste heat from the heat Ytreating portion of the process is used to effect Another object of theinvention resides in an so improved apparatus providinga combination ofelements for carrying out our process of reclaiming used lubricatingoils hereindisclosed.

A further object of the inventionis to provide. in a device fortreating'used lubricating oils, an 35 improved filtering aparatos whichcooperates with the otherelements of the combination to l produceamore-complete purification of the oil and which lends itself to safetyin the operation of the device and eliminates the danger of serious 40burns to the operator due to the handling of heated residues andthe`dripping ofheated oilsv from the :dltering aparatus.

A still further object of the invention resides in the provision of animproved device for utilizing the heat of the oil being treated, toprovideand admitto the oil, steam of the desired temperature andpressure and in the correct amount for satisfactory treatment.

Other objects and advantages of the invention will appear in thefollowing description of the preferred embodiment ofthe apparatus shownin the attached drawings and in the description of the preferred processof treating used crank case oil. In the attached drawings Fig. 1 is anelevation of the complete oil treating device;

Fig. 2 is an elevation, partly in section, of the treating chamber;

Fig. 3 is a fragmentary elevation of the lower portion of the treatingchamber with parts removed;

Fig. 4 is a sectional view of the lter door.

Referring more particularly to the drawings, I6 -indicates a heatexchanger in which treated oil is made to give up part of its heat tothe oil to be treated; II indicates a mixing chamber in which oil andlter material is mixed prior to charging into treating chamber; I 2indicates generally an oil treating chamber assembly; I3 indicatesgenerally the filter door and filter paper supplying assembly; I4indicates the condenser for condensing vapors from the oil treatingchamber; I5 indicates the receiving tank for the distillate from theAcondenser; and I5' indicates a metal contact filtration device for thetreated oil after it is passed through the heat exchanger.

The heat exchanger Iii comprises a tank I6 provided with an `inlet I1through which used crank case oil may be pumped or drained into the heatexchanger tank. A pipe coil i 8 is positioned Within the heat exchangertank and connected to the outlet of the filter door, asvhereinafterexplained. The other end of the coil I8 is connected to an outlet pipeI9 which leads to the contact filter I5'. The heat exchanger tank isprovided with an overflow pipe 20 and with an outlet pipe 2I. It is tobe noted that the outlet pipe 2|A is connected to the heat exchangertank at a point spaced from the bottom of the heat exchanger tank toprovide a settling chamber below the outletand that a drain 22 having avalve 23 is provided to empty the lowerportion of the heat exchangertank. The outlet pipe 2i is provided with a `manually operable quickaction valve 24-and this outlet pipeempties into the top of the mixingchamber II.

The mixing tank Il has an enlarged opening which `can be closed by thecap 25, the opening being provided for the purpose of allowing ameasured amount of oil treating material, for example, acid treated clayto be poured into the mixing chamber II. An agitating device operated bythe agitating lever 26 is provided for lsecuring an intimate mixturebetween the oil to be treated and the mixing material. A source y ofcompressed air 21 connected to the mixing chamber Il through airpressure regulator 28, valve 29 and pipe 38 allows air pressure to beapplied to the surface of the mixture in the treating chamber, to forcethe mixture through the I `suitable gaseous pressure may be utilized forthis purpose. A check valve 34 is provided in the pipe 3| to preventback pressure from the treating chamber`32 from interfering with theoperation ofthe mixing chamber II.

The treating chamber 32 which is positioned within the outer casing 33comprises a cylindrical portion 35 anda conical lower portion 36. Pines'31 extend vertically through the treating steam generating device 39 ispositioned within the treating chamber 32 and has its outer surface in'contact with the mixture contained in the treating chamber. This steamgenerating device comprises an outer casing 40 which is connected with asource of water 4I through a strainer 42, water pressure regulator 43,orifice fitting 44, a three-way valve and the pipe 46. A pipe 41 extendsthrough the bottom of the casing 48 to a point adjacent the top of thecasing and is connected to the outlet pipe 48 of the treating chamber 32through a ball check valve 49. The burner 38 surrounds the outlet pipe48 and is connected to a fuel supply through a pipe 5U which hasinterposed therein a fuel regulating valve 5I controlled by a thermostat52 responsive to the temperature of the mixture in the treating chamber.This thermostat can be utilized to discontinue the heating of themixture when a predetermined temperature is reached. A thermometer 53 isalso provided to give a visual indication of the temperature of themixture. 'An outlet 54 for vapor leads from the upper portion of thetreating chamber 32, through the outer casing 33 to an expansion chamber55. 'I'he expansion chamber 55 is connected through a pipe 56 to acooling coil 51 positioned within the condensing chamber I4. The otherend of the cooling coil is connected through a sight glass 58 to thereceiving tank I5. The condensing chamber I4 is provided withan inlet 59and an outlet 60 for a cooling medium such as water. The receivingchamber I5 is provided with a vent 6I which may, lead to any desiredlocation and an outlet 62 for the distillate.

As shown inr Figure 2, a manually operated valve 63 is provided in thelower outlet 48 o1' the treating chamber and has connected thereto apipe leading into a filter chamber 64 positioned below the outer casing33 and forming a support for the treating chamber assembly. A pipe 63'is connected to a source of compressed air through a pipe 21, pressureregulator 28, valve 64 and enters the filtering chamber 64 to provideair pressure for pressure filtration. As indicated above with respect tothe mixing chamber any other source of suitable gaseous pressure such assteam or any inert gas may be utilized. As shown in'Figure 1 the filterchamber 64 is supported upon a frame work 65 which also forms a supportfor the filter paper feeding device hereinafter de- Y scribed.

chamber and guide members 10 slidably mounted upon the guide pins andrigidly secured to the door plate 68, by means of bolts 1I permit thefilter door 66 to be moved vertically but maintain the door in ahorizontal position at all times. The door 66 is supported upon aspherical bearing member 12 which is drilled and internally threaded toreceive a threaded discharge pipe 13.

The pipe 13 is also threaded into the door plate 68 to form a rigidconnection between the bearing member 12 and plate 68. The bearingmember 12 is received in a semi-spherical socket 14 forming part of adoor closing beam 16. Beam 15 is pivotally supported at one end by alink 16 and has an extension 11 engaging one end oi' a counter-balancingspring 18 which has its other end engaging a bracket 18 mounted upon theframe 85. Link 18 is pivoted at 88 to a '15 when the beam approaches itsuppermost position. 'I'he link 82 is pivoted at 84 to a verticallylmovable member 85 slidably mounted in a bracket 88 secured to theillter chamber casing 84. 'Ihe slidable member 85 isprovided at itsupper end with a screw threaded extension (not shown) lupon which ismounted an internally threaded member 8,1 bearing upon the bracket 88. Adouble ratchet device 88 provided with a lever 88 is positioned abovethe member 81 and is effective to turn the internally threaded member 81in either direction at the will oi the operator.

'Ihe ltering device I3 is also provided with means for positioning afreshl supply of filter paper or cloth upon perforated plate 81 formingpart of the lter door and for removing the residue .from the lterchamber; In the embodiment shown, this device includes supports 88 and8| mounted upon the frame 65 and provided with notches for. receivingarbors upon which filter l paper rolls 82 and 83 are mounted. Superposedwebs of lter paper 84 are threaded across the top of the lter door 88 asshown in Figures 1 and3 and are re-rolled upon an arbor 85 journaled ina bearing V88 mounted-upon the frame 88. The arbor 85 is provided with acrank 81 for manual rotation. 'Ihe guide pins 81, upon which the'fllterdoor is slidably mounted; also' serve as guides for the filter paper.

The dischargepipe 13.from the iiltering device is connected throughflexible connections to the coil I8 o! the heat exchangerl8 by al pipe88. As described abovegthe coil I8 of the heat exchanger is connectedthrough pipe I8 to the upper portion of the contact ltration device I5.The contact filtration device I5 comprises an outer 'casing 88providingl a chamber which may .be nlled with copper or steelwool, orsimilar metalli'c material, having a large, contact surface and smallinterstices for the oil to illter through. A discharge pipe I88 leadsfrom the lower portion'v of the iliter I5 and discharges into anyconvenient container for the reconditioned oil.

The improved process which we employ to rel claim used crank case oilwill be described in connection with the operation, of the apparatusherein shown, but it is to be understood-"that other i'orms of apparatuscaribe used in carrying out our process.' In carrying out our process,used `.'I-l into the roll fromA 'throucl one oil is pumped or drainedthrough pipe heat 'exchanger chamber I8. Heated a prior 4treatingoperation 'is forced The heat thus made available` attacks grease andsind present in the crank case drainings, the

heavy 'non-mtering substances settle down and the lubricating or lighteroil separates upwardly 'auch that the heavy greases and sludge accumuthecoil I8 in the heat exchanger and l gives up some of its heat totleiltobe treated.

opening valve 24- is opened to anew the 4lubricating and lighter oils todrain into the mixing chamber. The overflow 28 in the heat exchangerchamber determines the amount of crank case drainings in the heatexchanger such that itis impossible to overload the mixing chamber andalso provides a vent so that the oil will readilyl flow from the heatexchanger. A calculated charge of acid treated clay or other -oiltreating substance is introduced into the mixing chamber and agitated soas to thoroughly incorporate the treating substance into the oil. Thecover 25 for the mixing chamber is `then screwed down tightly andcompressed air vintroduced into the pipe' 38 to force the mixturethrough the pipe 8i and check valve 34 into-a treating chamber 32.

Heat is then applied to the treating chamber by means of the burner 38and the temperature of the oil and treating material raised to substan-1tially`600 F. When the temperature reachessub- L stantially this point,the burner is shut on' and the three-way valve 45 actuated to admit acontrolled amount of water into the steam generator 48. The amount ofwateradmitted in a given time is determined by the water pressureregulator 43 and the oriiice iittlng 44 and the water thus admitted .isstrained through strainer 42 to prevent a deposition oi.' foreign matterin the pressure regulator, oriiice 44, valve 45 or steam generator 48.The water admitted to the steam generator -48 absorbs heat from the oilVsurrounding the steam generator and the resultant steam is collected bythe pipe 41 and injected into pipe 48 so as to pass upwardly through themixture contained in the treating chamber to agitate the t same andcarry -o'fl' vapors entrained therein. The formation of steam in thesteam generator will abstract heat from the mixture in the treatingchamber and the steam admitted to the treat` ing chamber will be at asomewhat lower temperature than the mixture. It will be seen that theeffect of the formation oi.' the steam and admission of the steamto thetreating chamber will cause a drop in temperature of the mixture `aswell as an agitation of the mixture.

During the heating oi.' the mixture and the subsequent agitation bysteam, the lighter Ifractions containedin the .mixture will'be driven 0Eas vapors contained in the condenser I4, andA received as a liquid inthe condensation tank I5.

When the mixture `has been agitated for a sufiicient length of time andthe temperature lowered to approximately 524 F. thefthree-way valve 45may b'e operated to disconnect the water sup ply from the steamgenerator and open thev generator to the atmosphere to relieve thepressure therein. The checkvalve 48 prevents the passage of any of themixture back to the steam generator 48.

Introducing the steaml after the heating operation does not have atendency to slow down the heating ofthe oil as would be the case if itwere introduced simultaneously with the heating-step..

nor does the steam, 4when employed, have a tendency to aid in crackingthe oil due to the-high and the temperature is'lowered sutllcientlytopre- 70 vent burning or charrlng of the iilter paper used.

other gases or vapors, for example an inert gas,

' Although steam is preferred, it is possible touse to agitate themixture and carry ofi' entrained 75 incoming crank case drainings in isalso to be noted that our During the heating steps a fresh supply offilter paper has been positioned upon the perforated plate 61 of thefilter door 66 and the filter door has been closed tightly against theopening 'in the filter chamber. The manually operated valve 63 is thenopened and the mixture allowed to ow into the filter chamber 64, afterwhich the valve 63 is again closed. Compressed air is then admitted intothe filter chamber through pipe63 to force the oil through the filterpaper. This pressure is also effective Vto force vthe filtered oilthrough the pipe 98, the heat exchanger coil i8 and the contact filterI5 to the outlet |90.

Upon completion of the filtering operation the ratchet device 88 isoperated by a lever 89 to relieve the pressure exerted by the beam 15against the filter door 66. The link 82 is then removed from the end 83of the beam 15 and the beam lowered manually carrying the filter doorwith it. Upon actuation of the crank 91, the used filter paper iswithdrawn from the perforated filter plate 61 and wound upon the arbor95. As a result of the rolling of the filter paper, the collection ofclay and carbon deposit on the paper is dumped into any convenientcontainer placed below the arbor 95. Also, a fresh supply of filterpaper is positioned upon the filter plate for the next filteringoperation. It will be noted that the filter paper, at all times,completely covers the top of the filter door and prevents any accidentalaccumulation of residue upon the door which might prevent the properclosing of the door. Also, it eliminates the necessity of the operatorhandling the heated residue or in any way coming in contact with theheated portions of the treating apparatus. After a fresh supply offilter paper has been positioned, the beam 15 is again raised, the link82 slipped over the end thereof and the ratchet device 88 actuated totighten the door against the bottom of the filter chamber. It improveddevice for closing the filter door eliminates the necessity of theoperators placing any portion of his body below the filter chamber andcoming in contact with heated oil dripping therefrom.

It will be noted that in our process the oil is filtered while hot,although the maximum temperature reached is somewhat reduced before'filtering in order to prevent fiashing and burning of the filter paper.The heat still contained in the oil is used to raise the temperature ofthe order, not only to conserve the heat necessary for treating the oil,but also to 'effect a preliminary separation of lubricating and lighteroils from non-filtering residues. Also, the heat exchanger serves tostill further reduce the temperature of the filtered oil such thatoxidation of the oil is inhibited.

We have discovered that oil treated,yas described above, still containsa considerable amount of very finely divided carbon and have discoveredthat this carbon can be removed by passing oil,

while at an elevated temperature through a device wherein it is broughtinto intimate contact with the metallic surface. The filtered oil, whenit leaves the heat exchanger, is at such a temperature that' passing itthrough a chamber containing copper or steel wool, or a similarsubstance, the finely divided carbon is deposited thereon and removedfrom the oil.

While we have described our preferred apparatus for the -re-claiming ofuse crank case oil and have described our preferred method of treatingused oil. it will be understood that the apparatus herein disclosed anddescribed'isfor the purpose of illustration only and that `our methodmay be carried out in other apparatus than that shown. It will alsobeunderstood that various changes may be made in the apparatus and methoddescribedwithin the scope of the following claims.

What we claim is: l

1. The herein described process of reclaiming used lubricating oils, thesteps which comprise,A

introducing used oils and a colloidal absorbent into a heated zone andheating the same to a high degree of temperature, discontinuing the heattreatment and while the oil remains in a condition introducing steamupwardly through the body thereof of a pressure sufficient to completelyagitate the mixture and carry off the released volatile constituentsthereof, withdrawing the oil from the heating zone and introducing it toa separate filtration zone and forcing the same, under pressure, througha filtration fabric, the said supply of steam tending to reduce thetemperature of the oil to an extent such that it will not scorch theltration'fabric during the filtration stage.

2. The herein described process of reclaiming used crank case oils, thesteps which consist in introducing used oils and a sufcient amount ofacid clay to restore it substantially to its original specification intoa heated zone, heating the mixture to a high temperature sufficient toboil off the light constituents, discontinuing the heating operation andintroducing an inert 'gas into the body of the mixture for the purposeof reducing its temperature to a predetermined extent, said inert gasbeing introduced under a sufficient pressure to completely agitate themixture, withdrawing the heated oil at its reduced temperature from theheating zone and introducing it into a filtration zone, applying aninert gas to the body of oil within the filtration zone for the purposeof accelerating its filtration therein.

3. The herein described process of reclaiming used oils, the steps whichcomprise, mixing a quantity of colloidal clay and used oil, thenceintroducing the mixture into a heated zone, where it is subjected to aheat treatment, discontinuing the heat treatment and reducing thetemperature of the heated oil to a predetermined degree by passing astream of inert gas upwardly which serves also to agitate the mixture,withdrawing the heated oil, at its reduced temperature from the heatedzone and subjecting it to a separate filtration zone whereby to separatethe clay and other non-lubricating constituents from the oil.

4. The herein described process of reclaiming used oils, the steps whichcomprise, mixing a quantity of colloidal clay and used oil, thenceintroducing the mixture into a heated zone, where it is subjected to aheat treatment, discontinuing the heat treatment thereafter reducing thetemperature of the oil'v by bringing water into inclirect heatexchanging relation with the oil to re-.

